Problem with layout

I have a calendar you can view here
http://alpha.clickablecommunity.com/Calendar.aspx
When the page loads initially the calendar views fine. However, as soon as you change the view i.e. to day or month the calendar gets wider. However, if you resize your browser window at all (doubleclick to resize down and then resize up again), then it goes back to the proper size. I am completely stumped on this one. Here is my code.
aspx
<%@ Page Title="" Language="vb" AutoEventWireup="false" MasterPageFile="~/MasterPage.Master" CodeBehind="Calendar.aspx.vb" Inherits="ClickableCommunity.Calendar" %>

I am trying to add some JS to add a rad tree that shows the apointments on client click. I still have the problem but it is on hold until I get this issue resolved because it is a higher priority. I'll post back when I have the issue. Thanks,

So that sort of fixed it. Now, however, when you change the view it stays on the page but get's moved almost to the edge. I put the margin where you said to. Any ideas why. You can still see it at the calendar2 link I provided earlier. At least it is on the page, just not spaced the same. I know these kinds of css questions are really difficult since IE likes to not follow the rules so I appriciate all of the help.

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